Toilet outlet seal

ABSTRACT

A seal  10  for a toilet outlet is described. The seal  10  comprises a body  12  and a deformable undercut lip  16.  The lip  16  is arranged so as to roll radially from the body  12  when subject to load, such as that exerted by a toilet outlet. The rolling motion of the lip ensures that the seal  10  deforms evenly and predictably when subject to load, so reducing the need for precise alignment of the toilet with the seal when installing the toilet.

FIELD OF THE INVENTION

[0001] The present invention relates to a seal for a waste outlet; andparticularly, but not exclusively, to a seal for a toilet outlet forconnecting a toilet to a soil pipe.

BACKGROUND OF THE INVENTION

[0002] In certain countries, it is conventional for a toilet wasteoutlet to be formed in the base of a toilet bowl, with the outletconnected to a soil pipe or a soil stack. With this arrangement, wastetravels vertically from the toilet into the soil stack, and a particularconfiguration of seal is required to connect the outlet to the soilstack. One common form of seal which is used is an annular wax seal,which receives the base of the toilet bowl within the soil stack inlet;the wax seal deforms to provide a seal against the toilet bowl. However,this deformation is not easily reversible, such that in the event thatthe toilet is, for example, misaligned during fitting and part of theseal experiences a high degree of compression, the seal cannot be easilyreformed and may have to be replaced. In practice, such damage to theseal is not likely to be apparent to the person fitting the toilet, andthe toilet will then be fitted with an imperfect seal. Furthermore, waxis a relatively unstable material, and may melt if the seal is exposedto even relatively low temperatures, for example, above 40° C., and maybecome brittle at lower temperatures.

[0003] An alternative arrangement makes use of a rubber or otherelastomeric seal ring, which sits between the toilet bowl outlet and thesoil stack. The seal ring is resiliently deformable, and is thusintended to deform when a toilet bowl is received therein to provide aseal. The seal ring includes an upper lip which abuts the toilet outletand the upper edge of the soil stack; the lip is pushed against the edgeof the soil stack by the weight of the toilet bowl to provide a sealSuch a seal ring is described in International Patent ApplicationWO00/09825. While this arrangement provides improved features whencompared with conventional wax seals, there are however disadvantageswith this type of resilient seal. In particular, the seal relies onpressure being applied by the toilet evenly around the circumference ofthe lip of the seal ring. In the event that the toilet is installedslightly off centre, or at a skewed angle, uneven deformation mayresult, which may lead to splaying or collapse of the lip and failure toform an effective seal. Thus, careful alignment and fitting of thetoilet is necessary for the seal ring to be effective.

[0004] It is among the objects of embodiments of the present inventionto obviate or alleviate these and other disadvantages of conventionalseal arrangements.

SUMMARY OF THE INVENTION

[0005] According to a first aspect of the present invention, there isprovided a seal comprising a generally tubular body for location betweentwo members to be connected, the body comprising a deformable lip forabutting one of the members to be connected, the lip being arranged suchthat the lip rolls radially when subject to axial compression.

[0006] Thus, the seal of the present invention may be located, forexample, between a toilet outlet and a soil pipe, and the compression ofthe lip caused by the weight of the toilet on the seal will cause thelip to roll radially. This arrangement not only allows an effective sealto form between the rolled lip and the toilet bowl, but the rollingaction reduces unpredictable slippage between the bowl and lip; thecontact between the toilet and the seal lip will be a rolling contact,and as such will be relatively unaffected by the frictional propertiesof the surfaces of the toilet or Lip. Further, the predictable rollingaction of the lip reduces the likelihood of buckling of the lip or otherparts of the body, which would affect formation of a seal, and reducesthe need for maintaining accurate alignment of the toilet on the sealduring installation.

[0007] Preferably the body is generally tapered, with an upper portionbeing of greater diameter than a lower portion. Preferably the body isgenerally frustoconical.

[0008] Preferably the lip is undercut; that is, the lip extends radiallybeyond a side wall of the body in the immediate vicinity of the lip. Thelip may also provide a generally cylindrical surface profile; that is,the profile of the lip forms a section of a cylindrical surface.Conveniently the surface profile of the lip is substantially half of acylinder, or hemicylindrical. Undercutting the lip in this manner servesto improve radial rolling of the lip. Most preferably, the highest pointof the lip, that is the part of the lip which first engages said one ofthe members to be connected, is positioned radially outwardly of amid-point of the adjacent body wall, to ensure that the lip rollsradially outwardly relative to the body wall.

[0009] Preferably the lip in use abuts only one of the members to beconnected. Conveniently the body further comprises a flange locatedspaced from the lip, for spacing the lip from the second member to beconnected. The flange is preferably substantially rigid, in that littleor no deformation of the flange occurs when the lip and flange are underload. The flange arrangement ensures that the lip is at least initiallyclear of the second member to be connected, and hence that the lip isfree to roll radially under pressure.

[0010] Preferably the body is substantially resilient. Conveniently thebody comprises elastomeric or rubber material. This allows the body toconform to the members to be connected. Alternatively, only the lip maybe substantially resilient; however, this is not a preferred embodiment.

[0011] Preferably the lip further comprises ridges or otherfriction-increasing formations thereon. Conveniently the ridges extendsubstantially circumferentially around the lip. This serves to increasethe friction between the toilet and the lip, and maintain the desiredrolling movement of the lip and formation and maintenance of a sealingcontact.

[0012] Preferably the body further comprises a sealing portion forforming a seal between the body and the second member to be connected.The sealing portion conveniently comprises a ridge or other protrusionon an outer surface of the body wall. This conveniently forms aninterference fit between the body and the second member to be connected,and hence will provide a sealing contact. The sealing portion ispreferably on a lower portion of the body.

[0013] According to a further aspect of the present invention, there isprovided a seal member comprising a body having a bore therethrough, thebody being for location between two members to be connected, the bodycomprising a lip for abutting one of the members to be connected, thelip being undercut.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] These and other aspects of the present invention will now bedescribed by way of example only and without limitation, with referenceto the accompanying drawings, in which:

[0015]FIG. 1 shows a side view of a seal in accordance with anembodiment of the present invention;

[0016]FIG. 2 shows a sectional side view on line B-B of FIG. 1;

[0017]FIG. 3 shows a perspective view of the seal of FIG. 1; and

[0018]FIG. 4 shows a sectional side view of the seal of FIG. 1 incombination with a toilet bowl and soil stack inlet.

DETAILED DESCRIPTION OF THE DRAWINGS

[0019] Referring first of all to FIGS. 1 to 3, these show a seal 10 inaccordance with an embodiment of the present invention The seal 10 isformed of a moulded hollow rubber body 12 having a generallyfrustoconical form. The body 12 has a lower seal 14 formed of athickened ring of rubber extending around the circumference of the body12.

[0020] On the upper portion of the body 12 is an undercut lip 16extending circumferentially around the body 12. The lip is generallysemicircular in cross-section, as can be seen best in FIG. 2, andcarries a number of circumferential ribs 18. Located on the body belowand spaced from the lip 16 is a circumferential shoulder or flange 20,which is generally solid.

[0021] In use, the seal 10 may be disposed, as illustrated in FIG. 4,between a toilet bowl 22 and a soil pipe 24. The soil pipe 24 may be setinto an opening in a floor (not shown), and leads into a soil stackwhich connects to a mains sewerage system. In installing the seal 10,the seal 10 is first placed into the pipe 24. The resilient nature ofthe rubber body 12 allows the seal 10 to be easily placed into the pipe24 by deformation of the body 12. The body 12 is lowered into the soilpipe 24 until the flange 20 rests on the upper edge of the soil pipe,formed as a pipe flange 26.

[0022] The lower seal 14 of the body 12 is sized to fit securely in aninterference fit into the soil pipe 24, and so create a seal with thepipe 24, preventing gases, fluids, and the like from escaping past theseal 10.

[0023] Once the seal 10 is located within the soil pipe 24, the toilet22 may be placed in position. The toilet 22 is lowered onto the lip 16of the seal 10. As the toilet 22 is lowered, the ribs 18 serve toincrease the friction between the toilet 22 and the lip 16, while theundercut formation of the lip 16 causes the lip 16 to roll radiallyoutwardly from the centre of the body 12 as load is exerted verticallythereon by the weight of the toilet 22.

[0024] The flange 20 is relatively heavy and incompressible, andsupports the weight of the toilet and the seal 10 itself, such that thewalls of the body 12 do not buckle. Further, the rolling action of thelip 16 provides for predictable and recoverable deformation of the lipas the toilet 22 is lowered onto the lip, such that precise alignment ofthe toilet is not necessary to prevent buckling of the seal; this effectis improved by the spacing of the lip 16 and the flange 20 such that thelip 16 contacts only the toilet 22, and not the soil pipe 24, and so isfree to roll outwardly without external constraint. In certainembodiments of the invention, under sufficient load, the lip 16 may rollsufficiently to form a tube contacting the flange 20.

[0025] Once the full weight of the toilet is supported by the seal 10,an effective seal is created between the lip and the toilet, sopreventing escape of noxious gases or fluids.

[0026] Thus, the present invention allows creation of an effective sealbetween a toilet and a soil pipe with a reduced risk of buckling orotherwise undesirable distortion of the seal, and hence a lesser needfor careful alignment of the toilet during fitting. Further, althoughthe invention has been primarily described with reference to sealingbetween a toilet and a soil pipe, it will be understood that the seal ofthe invention may be applied to any suitable members to be sealed.

[0027] In addition, given the frustoconical shape of the body 12, andits production from resilient rubber material, judicious selection ofdiameters of the upper and lower portions of the body 12 may allow thebody to be collapsed into itself for storage and transport.

[0028] It will be understood that the foregoing is for illustrativepurposes only, and that various modifications may be made to the sealdescribed herein without departing from the scope of the invention. Forexample, reference is made herein to outward rolling of the seal lip; inother embodiments, it may be more convenient for the lip to rollradially inwardly, for example when the lip is intended for locationwithin a member For this reason, reference should be made to theappended claims for determination of the scope of the invention.

What is claimed is:
 1. A seal comprising a generally tubular body forlocation between two members to be connected, the body comprising adeformable lip for abutting one of the members to be connected, the lipbeing arranged such that the lip rolls radially when subject to axialcompression.
 2. The seal of claim 1, wherein the body is generallytapered, with an upper portion being of greater diameter than a lowerportion.
 3. The seal of claim 1, wherein the body is generallyfrustoconical.
 4. The seal of claim 1, wherein the lip is undercut. 5.The seal of claim 1, wherein the lip provides a generally cylindricalsurface profile.
 6. The seal of claim 5, wherein the surface profile ofthe lip is substantially hemicylindrical.
 7. The seal of claim 5,wherein a highest point of the lip is positioned radially outwardly of amid-point of the adjacent body wall.
 8. The seal of claim 1, wherein thelip in use abuts only one of the members to be connected.
 9. The seal ofclaim 1, wherein the body further comprises a flange located spaced fromthe lip, for spacing the lip from the second member to be connected. 10.The seal of claim 9, wherein the flange is substantially rigid
 11. Theseal of claim 1, wherein the body is substantially resilient.
 12. Theseal of claim 1, wherein the body comprises elastomeric material. 13.The seal of claim 1, wherein the lip further comprisesfriction-increasing formations thereon.
 14. The seal of claim 1, whereinthe lip further comprises ridges thereon.
 15. The seal of claim 14,wherein the ridges extend substantially circumferentially around thelip.
 16. The seal of claim 1, wherein the body further comprises asealing portion for forming a seal between the body and the secondmember to be connected.
 17. The seal of claim 16, wherein the sealingportion comprises a protrusion on an outer surface of a body wall.
 18. Aseal member comprising a body having a bore therethrough, the body beingfor location between two members to be connected, the body comprising alip for abutting one of the members to be connected, the lip beingundercut.